A member of the French Foreign Legion, he was considered one of the historical Gaullists, and died aged 91 in the military hospital of the Val-de-Grâce in August 2007.

[3] He joined in London General Koenig's military staff and participated in the landings in Normandy in August 1944 and the Liberation of Paris.

[1] He was named the following year general secretary of the interministerial committee for Indochina and then head of staff of the high commissary of the Republic.

[1] Messmer began his high-level African service as governor of Mauritania from 1952 to 1954, and then served as governor of Ivory Coast from 1954 to 1956, when he briefly returned to Paris in the staff of Gaston Defferre, Minister of Overseas Territories who enacted the Defferre Act granting to colonial territories internal autonomy, a first step towards independence.

[4] Visiting de Gaulle in Paris, he was implicitly granted permission for his change of policies in Cameroon, which exchanged repression for negotiations with the UPC.

In that aim, the local population was rounded up in guarded villages located on the main roads that were controlled by the French Army.

[1] In 1960, Messmer visited Lisbon and expressed lament for the United Nations resolutions against colonialism and approved of the Estado Novo regime's hardline stance against decolonisation on the grounds that Portugal represented the last vestige of white Western civilisation on the African continent.

[5] Messmer gave permission for former Algerian War veterans to fight in Katanga against the newly independent Congo and United Nations peacekeeping forces.

[6] Along with the Minister of Research, Gaston Palewski, Messmer was present at the Béryl nuclear test in Algeria, on 1 May 1962 during which an accident occurred.

A member of the conservative wing of the Gaullist movement, he criticised the "New Society" plan of Prime Minister Jacques Chaban-Delmas and thus won the trust of Georges Pompidou, elected President in 1969.

[10] Due to President Georges Pompidou's illness, he dealt with the everyday administration of the country and adopted a conservative stance opposed to Chaban-Delmas' previous policies.

Henceforth, he stopped the liberalization of the ORTF media governmental organization, naming as its CEO Arthur Conte, a personal friend of Pompidou.

[1] In 1997 he testified as a witness during the trial of Maurice Papon, charged of crimes against humanity committed under the Vichy regime, and declared: "The time has come when the Frenchmen could stop hating themselves and begin to grant pardon to themselves".

[1] He also became elected as a member of the Académie française (the French language academy) in 1999, replacing a Gaullist comrade, Maurice Schumann.